Choanocyte is a characteristic of

Options

A. Annelida
B. Arthropoda
C. Porifera
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding Choanocytes**: Choanocytes, also known as collar cells, are specialized cells found in certain animals. They are characterized by a flagellum surrounded by a collar of microvilli.

2. **Identifying the Phylum**: Choanocytes are a defining feature of animals in the Phylum Porifera, commonly known as sponges.

3. **Function of Choanocytes**: These cells play a crucial role in the feeding process of sponges. The flagella of choanocytes create a water current that helps in drawing water into the sponge through small pores called ostia and expelling it through larger openings called oscula.

4. **Layers of Sponge**: In sponges, the body is organized into layers. The outer layer is called the pinacoderm, which is made up of flat cells, while the inner layer is known as the coenoderm, which is formed by choanocytes.

5. **Conclusion**: Therefore, the characteristic feature of choanocytes is that they are present in members of the Phylum Porifera.

**Final Answer**: Choanocytes are a characteristic of Phylum Porifera (sponges).

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